Spectral Reflectance Indexes Reveal Differences in the Physiological Status of Brassica oleracea with Contrasting Glucosinolate Content under Biotic Stress

Brassica species produce glucosinolates, a specific group of secondary metabolites present in the Brassicaceae family with antibacterial and antifungal properties. The employment of improved varieties for specific glucosinolates would reduce the production losses caused by pathogen attack. However, the consequences of the increment in these secondary metabolites in the plant are unknown. In this work, we utilized reflectance indexes to test how the physiological status of Brasica oleracea plants changes depending on their constitutive content of glucosinolates under nonstressful conditions and under the attack of the bacteria Xanthomonas campestris pv. campestris and the fungus Sclerotinia sclerotiorum. The modification in the content of glucosinolates had consequences in the resistance to both necrotrophic pathogens, and in several physiological aspects of the plants. By increasing the content in sinigrin and glucobrassicin, plants decrease photosynthesis efficiency (PR531, F_vF_m), biomass production (CHL-NDVI, SR), pigment content (SIPI, NPQI, RE), and senescence (YI) and increase their water content (WI900). These variables may have a negative impact in the productivity of crops in an agricultural environment. However, when plants are subjected to the attack of both necrotrophic pathogens, an increment of sinigrin and glucobrassicin confers an adaptative advantage to the plants, which compensates for the decay of physiological parameters.

Epigenetic and Phenotypic Responses to Experimental Climate Change of Native and Invasive Carpobrotus edulis

Despite the recent discoveries on how DNA methylation could help plants to adapt to changing environments, the relationship between epigenetics and climate change or invasion in new areas is still poorly known. Here, we investigated, through a field experiment, how the new expected climate scenarios for Southern Europe, i.e., increased temperature and decreased rainfall, might affect global DNA methylation in relation to phenotypic variation in individuals of clonal plant, Carpobrotus edulis, from its native (Southern African) and invaded (northwestern Iberian Peninsula) area. Our results showed that changes in temperature and rainfall induced phenotypic but not global DNA methylation differences among plants, and the climatic effects were similar for plants coming from the native or invaded areas. The individuals from the Iberian Peninsula showed higher levels of global methylation than their native counterparts from South Africa. We also observed differences between natives and invasive phenotypes in traits related to the pattern of biomass partitioning and to the strategies for water uptake and use and found an epigenetic contribution to phenotypic changes in some leaf traits, especially on the nitrogen isotopic composition. We conclude that the increased temperature and decreased rainfall projected for Southern Europe during the course of the twenty-first century may foster phenotypic changes in C. edulis, possibly endowing this species with a higher ability to successful cope the rapid environmental shifts. The epigenetic and phenotypic divergence that we observed between native and invasive plants suggests an intraspecific functional variation during the process of invasion. This result could indicate that phenotypic plasticity and global DNA methylation are related to the colonization of new habitats. Our findings reinforce the importance of epigenetic plasticity on rapid adaptation of invasive clonal plants.

Functional responses to climate change may increase invasive potential of Carpobrotus edulis

PREMISE

Biological invasions and climate change are major threats to biodiversity. It is therefore important to anticipate how the climate changes projected for Southern Europe would affect the ecophysiological performance of the invasive South African plant, Carpobrotus edulis (ice plant or sour fig), and its capacity to undergo rapid adaptive evolution.

METHODS

We manipulated the climate conditions in a field plot located on the island of Sálvora (northwest of the Iberian Peninsula) to establish a full factorial experiment with C. edulis plants transplanted from four native (southern African) and four invasive (northwestern Iberian Peninsula) populations. Throughout 14 months we measured growth and functional traits of this species under two temperatures (control vs. increased), and two rainfall levels (control vs. reduced).

RESULTS

Temperature increased photochemical efficiency and relative growth rate of C. edulis. Rainfall modulated some of the effects of temperature on C and N isotopic composition, and pigment contents. Invasive populations showed lower root mass allocation and higher survival rates, as well as increased water use efficiency, lipid peroxidation, chlorophyll, and xanthophyll cycle pigment contents than native populations.

CONCLUSIONS

The increased growth and physiological performances observed under our experimental conditions suggest that the expected climate changes would further promote the invasion of C. edulis. Differences between native and invasive genotypes in survival and functional traits revealed that populations have diverged during the process of invasion, what gives support to the invasiveness hypothesis. Our findings highlight the importance of analyzing intraspecific variability in functional responses to better predict how invasive species will respond to environmental changes.

Sclerotinia sclerotiorum Response to Long Exposure to Glucosinolate Hydrolysis Products by Transcriptomic Approach

White mold disease, caused by the necrotrophic fungus Sclerotinia sclerotiorum, affects Brassica crops. Brassica crops produce a broad array of compounds, such as glucosinolates, which contribute to the defense against pathogens. From their hydrolysis, several products arise that have antimicrobial activity (GHPs) whose toxicity is structure dependent. S. sclerotiorum may overcome the toxic effect of moderate GHP concentrations after prolonged exposure to their action. Our objective was to identify the molecular mechanism underlying S. sclerotiorum response to long exposure to two chemically diverse GHPs: aliphatic GHP allyl-isothiocyanate (AITC) and indole GHP indol-3-carbinol (I3C). We found that the transcriptomic response is dependent on the type of GHP and on their initial target, involving cell membranes in the case of AITC or DNA in the case of I3C. Response mechanisms include the reorganization of chromatin, mediated by histone chaperones hip4 and cia1, ribosome synthesis controlled by the kinase-phosphatase pair aps1-ppn1, catabolism of proteins, ergosterol synthesis, and induction of detoxification systems. These mechanisms probably help S. sclerotiorum to grow and survive in an environment where GHPs are constantly produced by Brassica plants upon glucosinolate breakdown. IMPORTANCEBrassica species, including important vegetable crops, such as cabbage, cauliflower, or broccoli, or oil crops, such as rapeseed, produce specific chemical compounds useful to protect them against pests and pathogens. One of the most destructive Brassica diseases in temperate areas around the world is Sclerotinia stem rot, caused by the fungus Sclerotinia sclerotiorum. This is a generalist pathogen that causes disease over more than 400 plant species, being a serious threat to economically important crops worldwide, including potato, bean, soybean, and sunflower, among many others. Understanding the mechanisms utilized by pathogens to overcome specific plant defensive compounds can be useful to increase plant resistance. Our study demonstrated that Sclerotinia shows different adaptation mechanisms, including detoxification systems, to grow and survive when plant protective compounds are present.

Domestication influences morphological and physiological responses to salinity in Brassica oleracea seedlings

Brassica oleracea cultivars include important vegetable and forage crops grown worldwide, whereas the wild counterpart occurs naturally on European sea cliffs. Domestication and selection processes have led to phenotypic and genetic divergence between domesticated plants and their wild ancestors that inhabit coastal areas and are exposed to saline conditions. Salinity is one of the most limiting factors for crop production. However, little is known about how salinity affects plants in relation to domestication of B. oleracea. The objective of this study was to determine the influence of domestication status (wild, landrace or cultivar) on the response of different B. oleracea crops to salinity, as measured by seed germination, plant growth, water content and mineral concentration parameters at the seedling stage. For this purpose, two independent pot experiments were conducted with six accessions of B. oleracea, including cabbage (group capitata) and kale (group acephala), in a growth chamber under controlled environmental conditions. In both taxonomic groups, differences in domestication status and salt stress significantly affected all major process such as germination, changes in dry matter, water relations and mineral uptake. In the acephala experiment, the domestication × salinity interaction significantly affected water content parameters and shoot Na+ allocation. At early stages of development, wild plants are more succulent than cultivated plants and have a higher capacity to maintain lower Na+ concentrations in their shoots in response to increasing levels of salinity. Different responses of domesticated and cultivated accessions in relation to these traits indicated a high level of natural variation in wild B. oleracea. Exclusion of Na+ from shoots and increasing succulence may enhance salt tolerance in B. oleracea exposed to extreme salinity in the long term. The wild germplasm can potentially be used to improve the salt tolerance of crops by the identification of useful genes and incorporation of these into salinity-sensitive cultivars.

Role of Major Glucosinolates in the Defense of Kale Against Sclerotinia sclerotiorum and Xanthomonas campestris pv. campestris

Glucosinolates (GSLs) are secondary metabolites present in Brassicaceae species implicated in their defense against plant pathogens. When a pathogen causes tissue damage, the enzyme myrosinase hydrolyzes GSLs into diverse products that exhibit antimicrobial activity against a wide range of bacteria and fungi in vitro. It was demonstrated that modulation of GSL content in vivo affects plant resistance to infection by pathogens in Arabidopsis. However, the roles of specific metabolites and how they interact with pathogens are poorly understood in Brassica crops. We previously developed a set of populations of Brassica oleracea var. acephala L. (kale) differing in content of three GSLs: the aliphatics sinigrin (2-propenyl [SIN]) and glucoiberin (3-methylsulphinylpropyl [GIB]) and the indolic glucobrassicin (3-indolylmethyl [GBS]). These populations can be used to study the effects of major GSLs in kale, with the advantage that genotypes within each selection have the same genetic background. This research aimed to explore the role of SIN, GIB, and GBS in the defense of kale against the necrotrophic fungus Sclerotinia sclerotiorum and the bacterium Xanthomonas campestris pv. campestris. Results showed that increasing the amount of a particular GSL did not always result in disease resistance. The effects of GSLs were apparently dependent on the pathogen and the type of GSL. Thus, the aliphatic SIN was inhibitory to infection by S. sclerotiorum and the indolic GBS was inhibitory to infection by X. campestris pv. campestris. Other factors, including the quantity and proportion of other metabolites modified during the pathogen infection process, could also modulate the degree of inhibition to the pathogen.

Prevalence of multiple sclerosis in Santiago de Compostela (Galicia, Spain)

Introduction

Multiple sclerosis (MS) is the most common central nervous system disease in young adults, and one of the leading causes of disability in this age group.

Objectives

To establish the prevalence and incidence of MS in Santiago de Compostela (Spain).

Material and methods

We performed a prospective, case-finding study on >90188 inhabitants, from 1 January 1998 to 15 September 2003, selected as day of prevalence. Sources of information were the University Clinical Hospital of Santiago, the hospitals and private clinics of the city, rehabilitators, pediatricians, ophthalmologists, psychiatrists, neurosurgeons, specialists in internal medicine, primary care physicians, association of patients of MS, social services and nongovernmental and religious associations. Informative days were programmed for the susceptible population, and campaigns were carried out in the media. All patients with Poser diagnostic criteria for MS, on the census of Santiago de Compostela as of 15 September 2003, were included in the study.

Results

On the day of prevalence, 71 patients with MS were registered on the census of Santiago de Compostela, therefore, the prevalence was 79 cases per 100000 inhabitants. The incidence of the disease in the study period was 5.3 cases per 100000 inhabitants and year.

Conclusions

The prevalence and incidence rates of MS found in Santiago de Compostela are the highest reported, to date, in Spain. Multiple Sclerosis 2007; 13: 262–264. http://msj.sagepub.com

Identification of Sources of Resistance to Xanthomonas campestris pv. campestris in Brassica napus Crops

Black rot, caused by Xanthomonas campestris pv. campestris, is one of the most important diseases affecting Brassica crops worldwide. Nine races have been differentiated in X. campestris pv. campestris, with races 1 and 4 being the most virulent and widespread. The objective of this work was to identify sources of resistance to races 1 and 4 of X. campestris pv. campestris in different Brassica napus crops, mainly in the underexplored pabularia group. Seventy-six accessions belonging to four B. napus groups were screened for resistance to two X. campestris pv. campestris races (1 and 4). The strain of race 1 used in this study was more virulent on the tested materials than the strain of race 4. No race-specific resistance was found to race 1. Most cultivars were susceptible except Russian kale, from the pabularia group, which showed some resistant plants and some other accessions with some partially resistant plants. High levels of race-specific resistance to race 4 were found in the pabularia group, and great variability within accessions was identified. Three improved cultivars (Ragged Jack kale, Friese Gele, and Valle del Oro) and four landraces (Russian kale, MBG-BRS0037, MBG-BRS0041, and MBG-BRS0131) showed plants with some degree of resistance to both races, which may indicate that race-nonspecific resistance is involved. These accessions could be directly used in breeding programs, either as improved cultivars or as donors of race-specific resistance to other Brassica cultivars.

When does acute pain become chronic?

The transition from acute to chronic pain appears to occur in discrete pathophysiological and histopathological steps. Stimuli initiating a nociceptive response vary, but receptors and endogenous defence mechanisms in the periphery interact in a similar manner regardless of the insult. Chemical, mechanical, and thermal receptors, along with leucocytes and macrophages, determine the intensity, location, and duration of noxious events. Noxious stimuli are transduced to the dorsal horn of the spinal cord, where amino acid and peptide transmitters activate second-order neurones. Spinal neurones then transmit signals to the brain. The resultant actions by the individual involve sensory-discriminative, motivational-affective, and modulatory processes in an attempt to limit or stop the painful process. Under normal conditions, noxious stimuli diminish as healing progresses and pain sensation lessens until minimal or no pain is detected. Persistent, intense pain, however, activates secondary mechanisms both at the periphery and within the central nervous system that cause allodynia, hyperalgesia, and hyperpathia that can diminish normal functioning. These changes begin in the periphery with upregulation of cyclo-oxygenase-2 and interleukin-1β-sensitizing first-order neurones, which eventually sensitize second-order spinal neurones by activating N-methyl-d-aspartic acid channels and signalling microglia to alter neuronal cytoarchitecture. Throughout these processes, prostaglandins, endocannabinoids, ion-specific channels, and scavenger cells all play a key role in the transformation of acute to chronic pain. A better understanding of the interplay among these substances will assist in the development of agents designed to ameliorate or reverse chronic pain.

Resistance of cabbage (Brassica oleracea capitata group) crops to Mamestra brassicae

Twenty-one cabbage (Brassica oleracea capitata group) varieties, including 16 local varieties and five commercial hybrids, were screened for resistance to the moth Mamestra brassicae L. under natural and artificial conditions in northwestern Spain. Resistance was assessed as the proportion of damaged plants and damaged leaves, leaf feeding injury, and number of larvae present. Correlation coefficients among damage traits showed that a visual scale (general appearance rating) should be a useful indicator of resistance. Most local varieties were highly susceptible to M. brassicae, whereas the commercial hybrids tested were resistant in terms of head foliage consumption and number of larvae per plant. Performance of varieties was similar under natural and artificial infestation although some of them performed differently at each year. Three local varieties (MBG-BRS0057, MBG-BRS0074, and MBG-BRS0452) were highly susceptible at both natural and artificial infestation conditions being MBG-BRS0074 the most damaged variety. Two local varieties (MBG-BRS0402 and MBG-BRS0535) and commercial hybrids were identified as resistant or moderately resistant to M. brassicae. Among them, 'Corazón de Buey' and 'Cabeza negra' were the most resistant and produced compact heads. These varieties could be useful sources of resistance to obtain resistant varieties to M. brassicae or as donors of resistance to other Brassica crops. The possible role of leaf traits, head compactness, and leaf glucosinolate content in relation to M. brassicae resistance is discussed.

Clinical picture of a patient with a novel PSEN1 mutation (L424V)

Young onset dementia raises concern about familial and non degenerative dementias. We describe a patient with early dementia. At the age of 26, a woman developed symptoms of anorexia nervosa, at 30 a memory and attention deficit, and at 34 abnormal behavior with impulsivity, aggression, and dysexecutive disorder. At 36 she showed aphasia, stereotyped behavior, hyperreflexia, grasping reflex, urinary incontinence, myoclonus, and seizures. Blood and cerebrospinal fluid were normal. Brain computed tomography and single photon emission computed tomography showed diffuse cortico-subcortical atrophy and frontotemporoparietal hypoperfusion. A Leu424Val mutation was present in PSEN1 gene. PSEN1 mutations can produce Alzheimer's disease, frontotemporal dementia, and dementia with Lewy bodies phenotypes, or a combination of them. It has been proposed that the mutation type and location may influence the molecular pathogenesis and thus PSEN1 would represent a molecular connexion between these entities. This case shows a novel PSEN1 mutation with outstanding amnesic and frontal symptoms.

[Clinical course of multiple sclerosis in patients treated with cytostatic drugs for cancer]

INTRODUCTION

The risk of side effects secondary to global and non-specific immune suppression has limited the systematic application of immunosuppressive therapy in multiple sclerosis (MS). However, when a patient with MS develops a cancer, cytostatic drugs as treatment for the neoplastic process may induce improvement not only of the cancer but also of MS.

CASE REPORTS

We present a series of four women with clinically defined MS and subjected to cytostatic therapy (cisplatin, 5-fluorouracil, leukovorin, adriamycin, tamoxifen and anastrozole) after the development of cancer: two presented breast cancer, one colon cancer, and the fourth parotid gland malignancy. Their clinical and neuroimaging course is described, following chemotherapy for the malignant disease. None of the patients have suffered further MS outbreaks. The four women have improved and remain clinically stable after neoplastic treatment. Magnetic resonance imaging showed persistence of the same lesion burden in three patients, and reduction in the other. At the present one patient receives weekly intramuscular interferon-beta 1a, whereas the other did not received any treatment.

CONCLUSIONS

Probably there are no specific cytostatics for MS. Immunosuppressive therapy could be a therapeutic option among patients with an aggressive clinical course.

Inheritance of White Mold Resistance in Phaseolus vulgaris × P. coccineus Crosses

The fungus Sclerotinia sclerotiorum, cause of white mold, is known to attack >400 plant species. It is a widespread problem in dry bean (Phaseolus vulgaris) in the United States, causing >30% average yield losses. Low to moderate levels of resistance are found in dry bean. However, some accessions of P. coccineus (commonly known as scarlet runner bean) possess a relatively higher level of resistance. Our objective was to verify the reaction of 13 known white mold-resistant P. coccineus germ plasms and determine inheritance of resistance in accessions PI 433246 and PI 439534. Pinto Othello was crossed with PI 433246, and the resulting interspecific F₁ was back-crossed onto Othello and allowed to produce F₂ seed. Similarly, pinto UI 320 was crossed with PI 439534. The F₁ was backcrossed onto UI 320 and allowed to produce F₂ seed. The two parents, F₁, F₂, and backcross to dry bean of each set were evaluated in the greenhouse using the straw test at Fort Collins, CO in 2004. All 13 P. coccineus accessions and the two F₂ also were evaluated using the modified petiole test at Kimberly, ID in 2005. All 13 P. coccineus accessions were variable in a 2002 straw test when rated for white mold reaction on a 1-to-9 scale, because the mean disease score ranged from 1.9 for PI 433246 to 4.4 for PI 189023 and 8.8 for the susceptible check Bill Z. For the petiole test, when rated on a 1-to-9 scale, the accessions exhibited an intermediate white mold score of 4 or 5 in 2005. In 2004, the susceptible check Othello exhibited a mean score of 7.9 compared with 3.4, 3.2, and 2.1 for PI 433246, UI 320, and PI 439534, respectively. The white mold reaction of PI 433246 and PI 439534 was dominant in their respective F₁. The F₂ segregation further indicated that white mold resistance in PI 433246 and PI 439534 was controlled by a single dominant gene. These two and other white mold-resistant P. coccineus accessions and selected breeding lines from the interspecific crosses should be useful for future improvement of white mold resistance of pinto and other market classes of dry and green or snap bean.

GC-FID determination of cocaine and its metabolites in human bile and vitreous humor

Gas chromatography was used in combination with flame ionization detection (GC-FID) to develop a method for determining cocaine and its two metabolites, benzoylecgonine (BEG) and ecgonine methyl ester (EME), in bile and vitreous humor. The method used a 12 m x 0.2 mm i.d. column of 0.33 microm film thickness packed with 5% phenylmethylsiloxane, and proadifen as a reference compound. Drug-free bile and vitreous humor samples were used to prepare solutions of the target compounds at concentrations over the range 0.1-4 microg ml(-1) that were subjected to solid-phase extraction through Bond Elut Certify columns and derivatized with 99:1 (v/v) N,O-bis-trimethylsilyltrifluoroacetamide (BSTFA)/trimethylchlorosilane (TMCS). Calibration graphs were highly linear, with correlation coefficients above 0.99 in all instances. Also, the precision of the method was found to be quite acceptable, with coefficients of variation less than 5% for bile and less than 7% for vitreous humor. The average extraction yields ranged from 73.6% to 91.2% for bile and from 71.5% to 92.2% for vitreous humor. The proposed method was used to analyse 26 samples of bile and as many of vitreous humor from individuals fatally poisoned by cocaine, whether alone or in combination with other drugs. The mean drug levels found were 0.75 and 1.54 microg ml(-1) for cocaine in bile and vitreous humor, respectively, 6.35 and 0.94 microg ml(-1) for BEG, and 2.18 and 0.61 microg ml(-1) for EME.

[Seasonal variations in the outbreaks in patients with multiple sclerosis]

INTRODUCTION

It has been suggested that there is an environmental factor at play in the aetiology and pathogenesis of multiple sclerosis (MS) that acts as an essential component of the disease process, and a number of studies also point to a relationship between the seasons of the year and the appearance of outbreaks.

AIMS

Our aim was to study the possible relation between seasonal variations and the appearance of outbreaks in patients with relapsing-remitting forms of MS.

PATIENTS AND METHODS

We studied 31 patients over the period between 1997 and 2002 and calculated the monthly and quarterly rate of incidence of outbreaks. The statistical evaluation of the results was performed by applying the Chi-squared test.

RESULTS

We observed a higher incidence of outbreaks in the summer months (more in June) and a lower incidence in winter (less in December), with statistically significant differences.

CONCLUSIONS

In our patients, outbreaks of MS are related to seasonal variations, with a higher number in the warmer months and fewer in the colder months.

[Time evolution of TNF-alpha, VCAM-1, IL-4, IL-10, neopterin and CD-30 in patients treated with interferon]

INTRODUCTION

Interferon (IFN) diminishes the outbreaks of multiple sclerosis (MS) and slows down its progression. Follow-up of patients is performed using clinical and resonance imaging parameters, and no biological markers are available that allow us to determine its efficiency.

AIMS

1. To discover the effects of IFN on the serum levels of TNF-alpha, IL-4, IL-10, VCAM-1, neopterin and CD-30 in patients with MS; 2. To determine how these modifications evolve over time; 3. To find out the clinical value of its determination in isolation.

PATIENTS AND METHODS

We studied 19 patients with MS who were clinically stable and undergoing IFN therapy. Samples were obtained every 3 months over a 2.5 year period and always immediately before injecting the drug. The ELISA method was used to determine interleukins.

RESULTS

Serum levels of neopterin, CD-30 and VCAM-1 were not modified, TNF-alpha levels oscillated regardless of the clinical status of the patient and IL-4 and IL-10 had a significant serum peak at 9-12 months after beginning treatment.

CONCLUSIONS

The existence of a significant IL-4 and IL-10 peak between 6 and 12 months of therapy indicates that IFN reaches its possible immunomodulatory effect after several months and, therefore, a poor initial clinical response must not be a reason for discontinuing medication. The specific determination of the serum levels of IL is not useful in following up patients treated with IFN.

[Cerebellar glioblastoma multiforme: a case report]

INTRODUCTION

Cerebellar glioblastoma multiforme (CGM) accounts for less than 1% of all intracranial glioblastomas; it spreads quickly locally, above all towards the brain stem and adjacent leptomeninges, and has a poor prognosis.

CASE REPORT

We report the case of a 55 year old patient who presented a continuous feeling of dizziness, instability and sickness, with occasionally vomiting and double vision that had started two months before being admitted to hospital. A physical exploration revealed hypaesthesia of the right side of the face, tactile and algesic hypaesthesia in the left side of the body and nystagmus in the bilateral horizontal gaze. Results of the general physical exploration were normal. A magnetic resonance (MR) brain scan revealed a 3 cm expansive lesion in the middle cerebellar peduncle and right cerebellar hemisphere, which was hypointense in T1 and hyperintense in T2. Administering contrast showed it to be heterogeneous, with irregular annular enhancement, and perilesional edema. Subtotal excision of the lesion was performed and pathological analysis allowed a diagnosis of glioblastoma multiforme to be made; radio and chemotherapy were continued.

CONCLUSION

CGM is infrequent and 46.7 years is the mean age of onset. 59% of tumours are located in the hemispheres, they tend to spread locally, and remote metastases have also been reported. Initial clinical manifestations are intracranial hypertension, and gait and balance disorders. Differential diagnosis is provided by MR and includes metastasis, infarction and abscesses. Treatment involves radical surgical excision followed by local radiotherapy. The use of chemotherapy has been reported but its role in the treatment of this entity is still not altogether clear.

[Cerebral atrophy in multiple sclerosis patients treated periodically with boluses of methylprednisolone]

INTRODUCTION

In the last years advances in the treatment of the remittant and secondary progressive forms of the multiple sclerosis (MS) have taken place. In the primary progressive forms (PP) the side effects of potentially useful drugs prevent their use; in some studies an improvement of the evolution with the intravenous administration of periodic pulses of methylprednisolone (MP) has been observed.

OBJECTIVE

To evaluate if periodic pulses of intravenous MP injected every 4-6 weeks increase the degree of cerebral atrophy of the patients with PP MS.

PATIENTS AND METHODS

We studied 11 patients with PP MS treated during 33 months with periodic pulses of intravenous MP. The degree of cerebral atrophy was evaluated in axial cuts of 10 mm of studies of magnetic resonance with the indices of Evans, bicaudate, bifrontal, frontal spears and bithalamic. The statistical evaluation of the results was made applying the test of Wilcoxon-Mann-Whitney.

RESULTS

There are not statistically significant differences in the degree of cerebral atrophy with any of the used indices.

CONCLUSIONS

Periodic pulses of intravenous MP do not accelerate the cerebral atrophy in patients with progressive forms of multiple sclerosis.

[Interferon beta in multiple sclerosis]

INTRODUCTION AND METHOD

The mechanism of action of interferons We do not know in the multiple sclerosis but, although exist discrepancies in relation to their degree of effectiveness, fundamentally the dose to use and the administration route, the three available ones have proven to be effective in the reduction of the number of the bouts. We reviewed the more important clinical tests made with three interferons in the remitent recurrent (RR) forms, the isolated neurologic syndromes and the secondary progressive (SP) forms of the disease and reviewed the comparative studies between interferons.

CONCLUSIONS

The three interferons are well tolerated although the intramuscular form produces less skin effects; in the RR forms the number of bouts are reduced in significant form. Only the study with 1a intramuscular was demonstrated effectiveness in the SP forms and with the subcutaneous IFN b 1b exists discrepancies between the European and the American studies. The early treatment with subcutaneous IFN b 1a slow down the evolution of the disease. Except in relation to the side effects, there are not evidence that the dose and the administration route are important in the effectiveness in the long term.

[Intercellular communication in the astrocyte culture as a measure of therapeutic efficacy in multiple sclerosis treated by interferon]

INTRODUCTION

Measurement of therapeutic efficacy in multiple sclerosis depends on the clinical and magnetic resonance findings on follow up. There are no biological markers. Measurement of interleukins and other markers of inflammation has not proved useful in the follow up of these patients. The response of astrocytes to mediators of inflammation gives rise to modification in their capacity for intercellular communication.

OBJECTIVE

To find whether culture of astrocytes in serum from patients with multiple sclerosis at different clinical stages and on different treatments gives rise to modification in intercellular communication.

PATIENTS AND METHODS

Astrocytes were cultured in serum from three patients with an untreated acute clinical episode of multiple sclerosis, and the results compared with those obtained after serum culture when the patients had been treated with interferon for a year. RESULTS. In astrocyte culture using serum from patients with an acute episode of multiple sclerosis, but not on treatment with interferon, there was a statistically significant reduction in intercellular communication as compared to astrocytes cultured with serum from these same patients treated with interferon for one year (*p< 0.05; **p< 0.01).

CONCLUSION

Measurement of the modifications in intercellular communication on astrocyte culture may be used as a marker for inflammatory activity in the serum of patients with multiple sclerosis, and therefore as an index of therapeutic efficacy.

[Spinal epidural abscess secondary to pharyngeal trauma due to food]

INTRODUCTION

In recent years the incidence of spinal epidural abscesses has increased. Early diagnosis is very important, since once neurological deficit has become established this is often permanent. The commonest aetiological agent is Staphylococcus. Pain and fever are often the only symptoms before acute neurological deterioration.

CASE REPORT

A 76 year old hypersensitive, diabetic man presented complaining of pain and a sensation of warmth in both arms. He had no fever or other symptoms. Some three weeks before admission to hospital a fish bone had become stuck in his pharynx, causing a purulent lesion there. This was treated with antibiotics. Cervical MR showed a mass at the level of C4 C5, compatible with epidural abscess. Following drainage and antibiotic treatment he recovered, with no sequelas. Staphylococcus was isolated from the purulent fluid.

CONCLUSIONS

The possibility of epidural infection must be remembered in patients with fever and nerve root pain. Early diagnosis and suitable treatment, combining both surgery and prolonged treatment with antibiotics, are essential to prevent permanent neurological damage.

Simultaneous high-performance liquid chromatographic determination of urinary mandelic and phenylglyoxylic acids as indirect evaluation of styrene exposure

Styrene is rapidly metabolised to mandelic acid (MA) and phenylglyoxylic acid (PGA), which are excreted in urine. In this work, we have developed a simple, sensitive and specific high-performance liquid chromatographic method with minor sample preparation procedures for the simultaneous determination of MA and PGA in urine of workers exposed to styrene. Moreover, urine samples from workers of two plastic factories were analysed, styrene exposure levels of the workers were estimated and data obtained from the two factories were compared.

Clinically manifested major health problems of crossbred dairy herds in urban and periurban production systems in the central highlands of Ethiopia

The major clinical diseases of crossbred dairy herds were investigated for two years in a milk shed in Addis Ababa. Animals in 38 herds were randomly selected and visited weekly. Diagnosis of diseases and causes of death were based on clinical observation. Disease conditions were categorized into 8 groups, the mean annual incidence for all diseases being 44.7%. Reproductive diseases and clinical mastitis were most frequently observed, whereas gastrointestinal disorders, respiratory tract diseases, locomotor disorders and metabolic diseases each occurred in less than 5% of the cattle. Specific infectious and miscellaneous disease conditions each had annual incidence of about 6%. Cows and young stock were most affected and diseases were more frequent in urban situations than in periurban situations. Herd size and season significantly influenced the incidence of disease but study year did not. The crude mortality rate was 4.2%.

[Pentoxifylline: is it useful in multiple sclerosis?]

INTRODUCTION

Pentoxifylline (PTX) is a phosphodiesterase inhibitor which has been found in studies in vitro to inhibit the production of Th-1 cytokines. It has been postulated that it might be used as a possible coadjuvant treatment for interferon in patients with multiple sclerosis. This would also reduce the potential side effects of interferon. OBJECTIVE. To show the efficacy of PTX in reducing the side effects of interferon, and in the functional improvement of these patients.

PATIENTS AND METHODS

We studied 18 patients with remitting-relapsing multiple sclerosis over a period of 18 months; nine patients were given PTX and interferon 800 mg/day simultaneously, and nine patients were treated with interferon alone. The clinical condition was evaluated every three months using the Expanded Disability Status Scale (EDSS) and the Neurological Score (NRS) scales.

RESULTS

We found no statistical improvement in the clinical course of EDSS and NRS in either group of patients after treatment for 18 months. The patients treated with PTX have fewer secondary effects due to interferon (fever and myalgia) during the first three months, but these differences between the groups subsequently disappear. In two patients PTX caused transient gastralgias and nauseas.

CONCLUSIONS

PTX may be useful as a coadjuvant drug with interferon during the first three months of treatment since some of the side effects of interferon may thus be reduced. However, there seems no justification for using PTX for a longer period since there is no functional improvement.

Reduction of fecal shedding of enterohemorrhagic Escherichia coli O157:H7 in lambs by feeding microbial feed supplement

Enterohemorrhagic Escherichia coli O157:H7, an emerging food-borne pathogen, has been implicated in several outbreaks in the US. Ruminants, including cattle, sheep and deer are reservoirs of E. coli O157:H7 and fecal shedding of the pathogen forms the vehicle of entry into the human food chain. We studied the efficacy of Lactobacillus acidophilus, Streptococcus faecium, a mixture of L. acidophilus and S. faecium and a mixture of L. acidophilus, S. faecium, Lactobacillus casei, Lactobacillus fermentum and Lactobacillus plantarum in reducing fecal shedding of E. coli O157:H7 by sheep experimentally infected with the pathogen prior to administration with the microbials. Following oral inoculation with 10(10)CFU of E. coli O157:H7, 30 Suffolk ram lambs were blocked by body weight (six blocks of five lambs each) and lambs within the block randomly assigned to five groups. The lamb groups were fed daily for 7 weeks a basal diet without microbial supplement (control) or the basal diet with L. acidophilus or with S. faecium or with a mixture of L. acidophilus and S. faecium or with a mixture of L. acidophilus, S. faecium, L. casei, L. fermentum and L. plantarum. The microbial supplements contained stabilized live naturally occurring bacteria and were mixed with the diet at the rate of 6.0x10(6)CFU per kilogram of diet. Fecal samples were collected weekly and analyzed for E. coli O157:H7 using modified tryptic soy broth with novobiocin as a pre-enrichement broth and cefixim-tellurite sorbitol MacConkey agar (CT-SMAC) as a selective media. E. coli O157:H7 was confirmed by its reaction with O157 and H7 antisera. E. coli O157:H7 was shed continuously and in varying numbers in the feces throughout the 7-week experimental period by all five groups. However, lambs administered a mixture of L. acidophilus, S. faecium, L. casei, L. fermentum and L. plantarum shed significantly lower (P=0.0211) average number of E. coli O157:H7 (2.3log(10)CFU per gram of feces per week) than the other lamb groups over the entire experimental period. S. faecium supplemented lambs were comparable (P=0.0884) to lambs fed a mixture of L. acidophulus and S. faecium in fecal shedding of the pathogen (3.5 versus 4.4log(10)CFU per gram of feces) but significantly lower (P=0.0001) than the control lambs (5.6log(10)CFU per gram of feces) and those supplemented with L. acidophilus (5.5log(10)CFU per gram of feces). Average daily gain (ADG) and gain to feed ratio (G:F) were significantly improved (P=0.0145) by the mixed culture microbials (163.0g and 0.33 for the control, 186.4g and 0.37 for L. acidophulus, 168.2g and 0.36 for S. faecium, 213.6g and 0.46 for L. acidophulus and S. faecium, and 219.1g and 0.44, respectively for L. acidophilus, S. faecium, L. casei, L. fermentum and L. plantarum supplemented lambs. The study indicates that supplementing lambs infected with E. coli O157:H7 with S. faecium or a mixture of S. faecium, L. acidophilus, L. casei, L. fermentum and L. plantarum in the diet can reduce total number of E. coli O157:H7 shed in the feces and improve animal meat production performance as well.

Low frequency of replication errors in primary nervous system tumours

OBJECTIVES

Automated DNA technology was used to analyze the incidence of microsatellite instability (MIN) among the most frequent types of adult primary CNS tumours and to determine its relation with clinicopathological characteristics.

METHODS

Fifty six gliomas, 32 meningiomas and 11 schwannomas were screened for size changes at eight microsatellite loci using fluorescent polymerase chain reaction (PCR) followed by fragment analysis in an automated sequencer. A tumour was considered as MIN+ when a different electrophoretic pattern between constitutional and tumour DNA was evidenced in one or more microsatellite markers and as replication error positive (RER+) when at least 25% of the markers analyzed (2/8) showed instability. The MIN phenotype was correlated with relevant clinical and pathological parameters.

RESULTS

Globally, instability was found in 19/767 analyses (2.47%), with a higher rate among tetranuceotide than dinucleotide repeats (chi(2) test, p=0.018). Ten gliomas (17.9%), two meningiomas (6.3%), and two schwannomas (18.2%) were MIN+, whereas one glioma (1.8%), two meningiomas (6.3%), and one schwannoma (9.1%) were classified as RER+. A possible association between microsatellite instability and a shorter duration of clinical course was found in meningiomas. The MIN+ phenotype was more frequent in spinal than intracranial schwannomas (Fisher's exact test, p=0.018). No other significant association with clinical or histological features was detected.

CONCLUSIONS

Although microsatellite instability can be demonstrated at a low rate in some primary CNS tumours, a true replication error phenotype (revealed by widespread microsatellite instability at numerous loci) is uncommon and unlikely to play an important part in the pathogenesis of these neoplasms. This form of instability was more frequent in tetranucleotide than in dinucleotide repeats. To our knowledge, this is the first report of MIN in schwannomas, where it was associated with the spinal localisation of the tumour.

Synthesis and herbicidal activity of N-oxide derivatives

As part of an ongoing program on the chemistry and biological activity of N-oxide-containing molecules, a number of novel 1,2, 5-oxadiazole N-oxide, benzo[1,2-c]1,2,5-oxadiazole N-oxide, and quinoxaline N,N'-dioxide derivatives were synthesized and evaluated for their herbicidal activity. Many of these compounds exhibited moderate to good herbicidal pre-emergence activity against Triticum aestivum. Dose-response studies were done on the more representative compounds (12, 20, and 26). The most active compound, butylcarbamoylbenzo[1,2-c]1,2,5-oxadiazole N-oxide, 26, displayed herbicidal activity at concentrations as low as 24 g/ha.

Assessing microsatellite instability with semiautomated fluorescent technology: application to the analysis of primary brain tumors

The replication error phenotype, revealed by the observation of widespread microsatellite instability (MIN), has been identified as a new mechanism of cancer susceptibility, and the comparison of the allele sizes of polymorphic microsatellite repeats between normal and tumor DNA is now frequently undertaken in colorectal and other human neoplasias. The lack of precise characterization of the electrophoretic profiles of microsatellites is one of the main sources of discord between the rate of MIN reported for the same type of tumor by different investigators. The recent introduction of fluorescent-based semiautomated microsatellite analysis allows a more accurate size comparison, but one or more artificial peaks, generated during polymerase chain reaction (PCR) and/or electrophoresis, are frequently detected along with the true allele peaks. The aim of this study was to characterize the most frequent artificial extra peaks in the short tandem repeats (STRs) used by us to assess MIN in human cancers. We analyzed eight microsatellite loci in 113 primary brain tumors. HumFibra/FGA exhibited the most frequent extra peak formation. For each microsatellite there is a characteristic pattern of artifact formation which must be recognized to avoid a false-positive diagnosis of MIN.

Characteristics of postradical neck pain syndrome: a report of 25 cases

The postradical neck pain syndrome has been briefly described in the literature, but detailed characterization has not been reported. To further define this syndrome, 25 patients with persistent pain for at least 1 month following neck dissection were evaluated. The sample consisted of 13 men and 12 women with moderate to severe pain ranging from 1 month to 27 years in duration. All patients had at least one type of neuropathic pain: spontaneous, continuous burning pain (81%), shooting pain (69%), and/or allodynia (88%). Neuropathic pain sites were within the distribution of the superficial cervical plexus (SCP). Regional myofascial pain was also common (72%). Seventeen patients agreed to undergo diagnostic local anesthetic injections. Ten of these patients had both neuropathic and somatic (myofascial) pain. Local anesthetic injection of the SCP temporarily eliminated all neuropathic pain in the 17 patients who underwent the procedure. The 10 patients who also had myofascial pain reported temporary relief of their somatic pain following myofascial trigger point injections (TPI). Criteria for the postradical neck pain syndrome are proposed: (1) persistent, nonprogressive neuropathic pain involving one or more branches of the SCP, which may be accompanied by (2) regional nonprogressive somatic pain associated with myofascial pain trigger points in head and neck muscles.

[Comparison of hypertensive and non-hypertensive lacunar infarcts]

INTRODUCTION

Arterial hypertension and hypohyalinosis of the arterias perforantes are said to be the commonest cause of lacunar infarcts, although other etiological factors and anatomo-pathological lesions are described more and more frequently. We designed a study to compare the clinical topographic and prognostic characteristics of patients with hypertensive and non-hypertensive lacunar infarcts.

MATERIAL AND METHODS

We selected 51 patients with lacunar infarcts: in 23 (45%) arterial hypertension was the only etiological factor recognized. In 28 (55%) other risk factors (16 diabetes mellitus, 17 cardiopathy, 8 hyperlipemia, 13 cigarette smoking and 11 alcoholism) were seen. We evaluated the form of presentation, the type of infarct and whether this was associated with headache. The degree of defect was determined on admission using the Canadian scale. The size of the infarct was measured on CT or RM, using whichever measurement was greater. The evolution of the condition was determined on the Canadian scale and the index of Barthel after three months.

RESULTS

Age and sex distribution was similar to both groups. Motor hemiparesia was the commonest lacunar syndrome and the distribution was similar. There was no difference in form of onset, association with headache or neurological defect between the hypertensive and non-hypertensive lacunar infarcts. The topographical distribution, the presentation of single or multiple lesions, the size of the infarcts and the prognosis were similar in both groups.

CONCLUSIONS

Lacunar infarcts, whether hypertensive or not, show no differences regarding clinical, neuro-radiological or evolutionary characteristics.

Proglumide as a morphine adjunct in cancer pain management

Proglumide, a cholecystokinin (CCK) antagonist, has been shown to have agonist effects at extremely low doses on both endogenous and exogenous opioid systems. To determine the effectiveness and the side effects of proglumide as an opioid agonist, a double-blind crossover study was conducted in 60 patients with cancer pain who were treated with opioid analgesics. Forty-three patients completed both treatment arms: (a) full analgesic dose plus placebo (the patient's usual analgesic dose, individualized to drug dose and route) and (b) one-half analgesic dose plus 50 mg of proglumide. An analysis of eight pain descriptors was performed to determine whether or not these treatments were associated with a difference in patients' pain perception. The level of patient anxiety differed between the two arms, but was inconsistent over time. There were no side effects detected with proglumide, as determined by clinical monitoring and patient questionnaire. No differences in pain perception were detected between the study arms. The latter finding is consistent with an augmentation of morphine analgesia, but without additional controls, the equivalency of the two arms cannot be determined with certainty. Nonetheless, this study suggests that proglumide may have use as an opioid adjunct in patients with cancer pain.

[Time for cerebral damage due to hyperglycemia in acute ischemia]

INTRODUCTION

Hyperglycemia increases morbimortality in cerebral infarcts. In animal models, this relationship is only seen during the initial moments of cerebral ischaemia. The time needed in humans for cerebral damage to occur due to hyperglycemia is not known.

MATERIAL AND METHODS

We included 194 patients admitted within 24 hours of the start of their first clinical episode of cerebral hemisphere infarction. The glucemia was determined on admission and after 24, 48 and 72 hours. The neurological defect was evaluated on the Canadian scale on the seventh day. The volume of the infarct was determined on a second CT scan done between the fourth and seventh days after the episode.

RESULTS

There was a positive association between the volume of the infarct and the glycemias on admission and after 24 hours, but this was not seen in later determinations. The difference in scoring, on the Canadian scale, on the seventh day, between patients with glycemias above or below 120 mg/dl decreased from the time of admission up to the time samples were taken 72 hours later. However, statistical significance persisted during the whole period studied. Nevertheless, in a logistic regression model, the glycemia on admission was the only determination associated with the Canadian scale on the seventh day (OR = 1.02; IC 95% = 1.01-1.02).

CONCLUSIONS

There is a clear association between hyperglycemia and the worst stage of the infarct, and this is most intense in the first hours after onset of the clinical features.

Experience with gabapentin for neuropathic pain in the head and neck: report of ten cases

BACKGROUND AND OBJECTIVES

Gabapentin is an oral antiepileptic agent with an unknown mechanism of action. Recent case reports have suggested that gabapentin may be effective in the treatment of a variety of neuropathic pain states. This report presents baseline and follow-up data on ten patients who were treated with gabapentin when other pharmacologic interventions failed to relieve their neuropathic pain.

METHODS

Ten patients referred for treatment of unrelieved neuropathic pain in the head and neck region were included in this study. Baseline and follow-up information included measures of pain intensity and pain quality. All of the patients were started on 300 mg gabapentin three times per day, though daily doses of up to 2400 mg were required for pain relief.

RESULTS

Eight of the ten patients had no neuropathic pain on follow-up, whereas the remaining 2 patients reported only partial relief at follow-up. None of the patients complained of side effects. Gabapentin was effective in alleviating steady burning pain as well as lancinating pain and allodynia.

CONCLUSIONS

The results suggest that gabapentin may be effective in the management of some cases of neuropathic pain in the head and neck. However, controlled, double-blind longitudinal studies are needed to evaluate this possibility.

[Familial strio-pallido++-dentate calcification]

INTRODUCTION

Calcification of the dentate nucleus of the cerebellum may be seen on cerebral CT in 0.3-0.5% of patients with no symptoms or extra-pyramidal signs. Although there are many causes, some cases show a family incidence. Clinical cases. We present two cases, mother and son, in whom the predominant clinical findings were poor language and a bilateral extrapyramidal syndrome. Laboratory tests, hormone and immunological studies were normal. In both patients cerebral CT showed bilateral calcification of the basal nuclei and dentate nuclei of the cerebellum.

DISCUSSION

Our patients fulfilled the clinical and neuro-imaging criteria described in familial strio-pallido-dentate calcification. There is no relationship between the duration and intensity of symptoms, and the extension of the calcification. However, all patients with calcification show clinical features. The predominant features are poor language and a bilateral extra-pyramidal syndrome. These observations indicate that in patients with calcification of the basal ganglia and dentate nuclei of the cerebellum it is necessary to study first degree relatives in order to identify the condition.

[A study of bilingual Galician-Castillian aphasic patients]

INTRODUCTION

Aphasia in bilingual persons has some striking peculiarities. Most studies have been carried out in mono-lingual societies, where the second language has usually been learnt after immigration. In Galicia, linguistic closeness and simultaneous learning of Galician and Castilian languages permits the testing of neuropsychological theories conceived in other circumstances.

OBJECTIVE

In aphasic bilingual Galician-Castilian patients we studied how this affected denomination, designation and translation, different modes of recovery, variables associated with differential affectation, the presence and influence of specific phenomena of aphasia in bilingual persons on changes in dominance and mixing of the languages. Material and methods. We selected 49 patients, 29 men and 20 women aged between 32 and 85 years old. We analyzed the variables associated with differential affectation: types of aphasia, size and site of the lesion, aetiology, age, educational level, and the presence and influence of phenomena specific to aphasia in bilingual persons.

RESULTS

The test most affected was translation, to a lesser extent denomination, and finally designation. Capacity for recovery is greater in the dominant language. Translation recovers better than denomination and this better than designation. We found no changes in dominance, no selective loss of either language but have seen some interference in the non-dominant language.

CONCLUSIONS

The two languages are seen to be recovered equally, as were other languages previously studied in aphasiology.